Department of Plant Breeding, Swedish University of Agricultural Sciences, P.O. Box 101, 23053, Alnarp, Sweden,
Theor Appl Genet. 2014 Sep;127(9):1963-73. doi: 10.1007/s00122-014-2352-5. Epub 2014 Aug 12.
Identification of novel resistance QTL against wheat aphids. First QTL-resistance report for R. padi in wheat and chromosome 2DL for S. graminum . These sources have potential use in wheat breeding. The aphids Rhopalosiphum padi and Schizaphis graminum are important pests of common wheat (Triticum aestivum L.). Characterization of the genetic bases of resistance sources is crucial to facilitate the development of resistant wheat cultivars to these insects. We examined 140 recombinant inbred lines (RILs) from the cross of Seri M82 wheat (susceptible) with the synthetic hexaploid wheat CWI76364 (resistant). RILs were phenotyped for R. padi antibiosis and tolerance traits. Phenotyping of S. graminum resistance was based on leaf chlorosis in a greenhouse screening and the number of S. graminum/tiller in the field. RILs were also scored for pubescence. Using a sequence-based genotyping method, we located genomic regions associated with these resistance traits. A quantitative trait locus (QTL) for R. padi antibiosis (QRp.slu.4BL) that explained 10.2 % of phenotypic variation was found in chromosome 4BL and located 14.6 cM apart from the pubescence locus. We found no association between plant pubescence and the resistance traits. We found two QTLs for R. padi tolerance (QRp.slu.5AL and QRp.slu.5BL) in chromosomes 5AL and 5BL, with an epistatic interaction between a locus in chromosome 3AL (EnQRp.slu.5AL) and QRp.slu.5AL. These genomic regions explained about 35 % of the phenotypic variation. We re-mapped a previously reported gene for S. graminum resistance (putatively Gba) in 7DL and found a novel QTL associated with the number of aphids/tiller (QGb.slu-2DL) in chromosome 2DL. This is the first report on the genetic mapping of R. padi resistance in wheat and the first report where chromosome 2DL is shown to be associated with S. graminum resistance.
鉴定抗小麦蚜虫的新 QTL。首次报道小麦中 R. padi 的 QTL 抗性和 S. graminum 的 2DL 染色体。这些资源在小麦育种中有潜在用途。麦长管蚜（Rhopalosiphum padi）和禾谷缢管蚜（Schizaphis graminum）是普通小麦（Triticum aestivum L.）的重要害虫。抗性资源遗传基础的特征对于促进抗虫小麦品种的发展至关重要。我们检查了 Seri M82 小麦（敏感）与合成六倍体小麦 CWI76364（抗性）杂交的 140 个重组自交系（RILs）。RILs 对 R. padi 抗生性和耐受性性状进行了表型分析。温室筛选中叶片黄化和田间每分蘖上的 S. graminum 数量用于鉴定 S. graminum 抗性。RILs 还根据绒毛进行评分。使用基于序列的基因分型方法，我们定位了与这些抗性性状相关的基因组区域。在染色体 4BL 上发现了一个与 R. padi 抗生性（QRp.slu.4BL）相关的数量性状位点（QTL），解释了 10.2%的表型变异，与绒毛位点相距 14.6 cM。我们没有发现植物绒毛与抗性性状之间的关联。在染色体 5AL 和 5BL 上发现了两个与 R. padi 耐受性相关的 QTL（QRp.slu.5AL 和 QRp.slu.5BL），3AL 染色体上的一个位点（EnQRp.slu.5AL）与 QRp.slu.5AL 之间存在上位性互作。这些基因组区域解释了约 35%的表型变异。我们重新映射了先前报道的 S. graminum 抗性基因（假定为 Gba）在 7DL 上的位置，并在染色体 2DL 上发现了一个与每分蘖上的蚜虫数量相关的新 QTL（QGb.slu-2DL）。这是首次报道小麦中 R. padi 抗性的遗传图谱，也是首次报道染色体 2DL 与 S. graminum 抗性相关的报道。
